Do Peanuts Contain High Oxalates? An In-depth Guide

According to the National Kidney Foundation, calcium oxalate stones are the most common type of kidney stone. While a diet high in certain foods can increase risk, many are curious: do peanuts contain high oxalates?

Quick Summary

This article examines the oxalate content of peanuts, distinguishing between raw and roasted varieties, and details how they can affect individuals prone to calcium oxalate kidney stones. It covers comparative oxalate levels in different nuts, methods to reduce oxalate intake, and best practices for incorporating peanuts into a healthy diet.

Key Points

• High in Oxalates: Peanuts are considered a high-oxalate food, with roasted varieties containing higher levels than raw.

• Risk for Kidney Stones: For individuals prone to calcium oxalate kidney stones, excessive peanut consumption can increase risk, while moderate intake is generally safe.

• Dietary Management is Key: Strategies like pairing peanuts with calcium-rich foods can reduce oxalate absorption in the gut.

• Smart Preparation: Boiling and soaking raw peanuts can leach out some of the soluble oxalate content, making them a safer option.

• Hydration is Crucial: Maintaining adequate fluid intake is the most effective way to prevent kidney stone formation, regardless of oxalate intake.

• Lower Oxalate Alternatives: For those needing to reduce oxalate intake further, alternatives like walnuts, pecans, and macadamia nuts are lower in oxalates.

Understanding Oxalates and Their Impact

Oxalates, or oxalic acid, are naturally occurring compounds found in many plant-based foods, including fruits, vegetables, nuts, and legumes. For most healthy individuals, oxalates are not a concern and are simply excreted by the body. However, for people prone to calcium oxalate kidney stones, high oxalate intake can be problematic. These compounds bind with calcium, forming insoluble crystals that can accumulate in the kidneys and lead to stone formation.

The Oxalate Content of Peanuts

When asking, "do peanuts contain high oxalates?", the short answer is yes, they are generally considered a high-oxalate food.

• Raw Peanuts: The oxalate content can vary, but research has shown that raw peanuts have a significant amount. A study on the available oxalate content of nuts found that peanuts had moderate levels of intestinal soluble oxalate, which is the type that gets absorbed by the body.
• Roasted Peanuts: Roasting can actually increase the concentration of oxalates in peanuts. One study noted that roasted peanuts contained nearly 2.5 times more oxalates than raw peanuts, with a concentration of 187mg per 100g serving.
• Peanut Butter: As a concentrated form of peanuts, peanut butter also contains a notable amount of oxalates. However, research suggests that the total oxalate value can vary depending on the processing and whether it includes added salt and sugar. It's important to read labels and opt for unsalted, unsweetened versions where possible.

Comparison of Oxalate Content in Nuts

While peanuts are a legume and not a tree nut, they are often compared in dietary discussions. Here is a comparison of oxalate levels in a 1-ounce serving of various nuts and legumes based on available data:

Food	Oxalate Content (mg/1 oz serving)	Relative Oxalate Level
Peanuts	27	High
Almonds	49-64	Very High
Cashews	30-49	High
Walnuts	~6	Moderate/Low
Pecans	Very Low to Moderate	Low
Macadamia Nuts	Very Low	Low

This table provides a general comparison, but oxalate content can vary based on factors like variety, preparation, and growing conditions.

Reducing Oxalate Intake from Peanuts

For those who need to manage their oxalate intake but still want to enjoy peanuts, several strategies can help:

• Pair with Calcium-Rich Foods: Eating peanuts with a source of dietary calcium, like cheese or yogurt, can significantly reduce the amount of oxalate absorbed by the body. Calcium binds with oxalates in the intestines, preventing them from being absorbed into the bloodstream and excreted in the kidneys.
• Boil Raw Peanuts: Boiling is an effective method for reducing soluble oxalate levels. The oxalates leach into the water, and discarding the water after boiling can lower the final oxalate content.
• Soak Nuts and Peanuts: Soaking nuts in water for several hours before consumption can also help leach out some soluble oxalates.
• Moderate Consumption: The simplest method is to control portion sizes. A small handful of peanuts as part of a balanced meal is less likely to cause issues than large, daily quantities.

The Role of Hydration and Overall Diet

Beyond managing oxalate intake from specific foods, proper hydration is crucial for preventing kidney stones. Drinking plenty of fluids, especially water, helps dilute stone-forming substances in the urine. Additionally, adopting a well-rounded, lower-sodium diet is often recommended by healthcare professionals for kidney stone prevention. Limiting excess sodium can help reduce the amount of calcium the kidneys excrete.

Conclusion: Navigating Peanuts on a Low-Oxalate Diet

While peanuts do contain high oxalates, their consumption doesn't have to be entirely eliminated for most people. For those susceptible to kidney stones, the key lies in moderation and smart dietary pairings. Understanding the oxalate content, particularly the higher levels in roasted varieties and processed peanut butter, allows for informed choices. By combining peanuts with calcium-rich foods and ensuring adequate hydration, individuals can still enjoy this nutritious legume while mitigating the potential risks associated with high oxalate intake. Always consult with a healthcare professional or registered dietitian for personalized dietary advice, especially if you have a history of kidney stones.

Can peanuts cause kidney problems? An in-depth look at oxalate concerns

Peanuts can cause problems like acute oxalate nephropathy in some sensitive individuals, particularly with excessive consumption. However, this is not common. The main concern relates to calcium oxalate kidney stones, where the high oxalate content can contribute to stone formation in predisposed individuals. A balanced approach is recommended.

Is roasted or raw peanut better for oxalate content?

Raw peanuts typically contain less oxalate than roasted ones, though both are considered high-oxalate foods. The roasting process can significantly increase the oxalate concentration.

What are some low-oxalate alternatives to peanuts?

Lower-oxalate nut and legume options include macadamia nuts, walnuts, pecans, and chestnuts. Pumpkin and sunflower seeds are also good, lower-oxalate choices.

Does pairing peanuts with calcium reduce the risk of kidney stones?

Yes, pairing peanuts with calcium-rich foods like yogurt, milk, or cheese helps. The calcium binds with the oxalates in the stomach and intestines, reducing the amount of oxalate absorbed by the body.

How much is too much when eating peanuts and oxalates?

For people prone to calcium oxalate kidney stones, it's often recommended to aim for less than 100 milligrams of oxalates per day. Since a 1-ounce serving of peanuts can contain around 27mg of oxalate, moderation is key.

Can soaking peanuts reduce their oxalate content?

Yes, soaking raw peanuts can help reduce their soluble oxalate content. For the most effective reduction, discard the soaking water and rinse the peanuts thoroughly.

Should I avoid all high-oxalate foods if I'm at risk for kidney stones?

No, complete avoidance is not usually necessary or recommended. A doctor or dietitian will typically advise moderation rather than elimination. It's more important to manage overall oxalate intake, pair high-oxalate foods with calcium, and maintain excellent hydration.

Citations

• National Kidney Foundation. "Kidney Stone Diet Plan and Prevention." (October 9, 2025)
• Food Struct. "Peanut Nutrition & Calories - Complete Data of All Nutrients." (October 6, 2023)
• National Institutes of Health (NIH). "Peanut-induced acute oxalate nephropathy with acute kidney injury." (May 24, 2014)
• ResearchGate. "Available oxalate content of nuts." (June 2013)
• Mayo Clinic. "Kidney stones - Symptoms and causes." (April 4, 2025)
• National Institutes of Health (NIH). "Eating, Diet, & Nutrition for Kidney Stones." (Retrieved October 13, 2025)
• Dr. Berg. "Low-Oxalate Nuts: Best Picks for Kidney Health." (April 9, 2025)
• Nephrology Associates. "Low Oxalate Diet." (Retrieved October 13, 2025)

Frequently Asked Questions

What is the oxalate content of roasted peanuts?

Roasted peanuts generally have a higher oxalate concentration than raw peanuts. One study reported that roasted peanuts contain about 187mg of oxalates per 100g serving.

Are all types of nuts high in oxalates?

No, oxalate content varies significantly among different types of nuts and legumes. While almonds and cashews are also high, nuts like walnuts, pecans, and macadamia nuts have considerably lower levels.

How can I reduce the oxalates in my peanuts?

Boiling raw peanuts and discarding the water is an effective method. Soaking raw peanuts and rinsing them thoroughly before eating can also help reduce the soluble oxalate content.

What happens if I eat high-oxalate foods like peanuts without enough calcium?

Without enough calcium to bind with the oxalates in the digestive tract, more oxalates are absorbed into the bloodstream. This can increase the amount of oxalate in the urine, raising the risk of forming calcium oxalate kidney stones in susceptible individuals.

Can I still eat peanut butter on a low-oxalate diet?

Yes, but in moderation. Choose natural, unsalted, and unsweetened varieties. As with whole peanuts, pair it with a calcium source to minimize oxalate absorption. Control your portion size carefully.

Does cooking affect the oxalate content of peanuts?

Yes, but differently depending on the method. Boiling is effective at removing oxalates, as they leach into the water. Roasting, however, can concentrate oxalates and increase their content.

How do peanuts compare to other high-oxalate foods like spinach?

While peanuts are high in oxalates, they are generally lower than foods like spinach. For example, a 1-ounce serving of peanuts has significantly less oxalate than a cup of raw spinach.

What are the first signs that I might have an oxalate-related issue?

In sensitive individuals, potential signs of oxalate-related issues could include kidney stone symptoms such as severe pain in the side and back, pain during urination, or discolored urine. Acute oxalate nephropathy from excessive intake is rare but serious. Consult a healthcare provider if you have any concerns.